An adjusting system of this type is known from DE 20 2004 011 388 U1 and comprises a lower rail that can be mounted rigidly to the vehicle and an upper rail that can be mounted to the vehicle seat and that is displaceable along the lower rail. The displaceability of the upper rail along the lower rail makes possible adjustment of the vehicle seat connected to the upper rail in the longitudinal direction of the rails. For fixing of the upper rail in a desired adjustment position with respect to the lower rail, a locking device for locking the upper rail to the lower rail is provided. The adjusting system further comprises a memory module fixed alternately with respect to the seat or to the vehicle, which has a movable blocking catch for forming a positive lock with the lower rail. A control lever mounted firmly to the seat is also provided for actuating the blocking catch. Finally, the adjusting system also includes an actuating means, mounted firmly to the seat, for unlocking the locking device.
The memory module is used for mechanically storing a set longitudinal seat position if the vehicle seat has to be temporarily adjusted longitudinally. Such a temporary longitudinal adjustment of a vehicle seat is necessary, for example in two-door passenger cars or in minibuses, in order to facilitate entry and egress for a passenger in the rear of the vehicle.
For storing the set longitudinal seat position, the seat-mounted control lever is coupled to an actuating mechanism for temporarily displacing the vehicle seat longitudinally, such as an entry or egress mechanism. If the vehicle seat is displaced longitudinally for entry or egress, the control lever is moved from its locking or latching position which it forms with the memory module, whereby the memory module is uncoupled from the vehicle seat. At the same time, the blocking catch of the memory module is actuated in order to form a positive lock with the lower rail. In other words, in the event of a temporary longitudinal displacement of the vehicle seat, the memory module is stopped in a fixed position on the lower rail. By means of the stopped position of the memory module on the lower rail, the preset longitudinal seat position is stored. According to DE 20 2004 011 388 U1, the mechanism for folding the backrest of the vehicle seat is used as the actuating mechanism which triggers stopping of the memory module.
Furthermore, a similar adjusting system is known from DE 20 2006 005 103 U1, although the respective memory modules differ from one another in detail.
If the vehicle seat is pushed back again after stoppage of the memory module, the control lever, through suitable shaping, again forms a positive lock with the memory module at the stopped position and unlocks the positive lock between the blocking catch and the lower rail. The vehicle seat has again reached its original position.
According to DE 20 2004 011 388 U1 and DE 20 2006 005 103 U1, the blocking catch of the memory module is substantially in the form of a rotary lock which, upon suitable actuation, forms a positive lock with the recesses of the lower rail. For this purpose, the blocking catch engages either by means of blocking lugs in openings of the lower rail, or receives the bridges of the lower rail located between the openings in a correspondingly formed recess.
According to DE 20 2004 011 388 U1, the actuating mechanism for temporary longitudinal displacement of the vehicle seat, for example the mechanism for folding the backrest, is connected to the seat-mounted actuating means for unlocking the locking device. This is because, in a set longitudinal seat position, the upper rail is locked to the lower rail by means of the locking device, so that the vehicle seat would not be displaceable.